The jjjtrain site is tops for general info.
What a sharp/ dull tool sounds like- What I do is use a microphone which I took apart and blu- tacked to the spindle housing. I use headphones to listen to the tool cutting- it's a huge advantage. I daresay you could stick the output into your PC or even a tape recorder to play it back to your students?
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I love deadlines- I like the whooshing sound they make as they fly by. |